The use of intravenous fluids for management of mast cell disease

I get frequent consult requests from patients specifically around the use of IV fluids to treat mast cell disease. I am often asked to provide references for papers that show its use and benefit. I am not able to provide any such references because there are none. There has been no organized study for the use of intravenous fluids to manage symptoms from mast cell disease.

Despite this fact, use of intravenous fluids in mast cell disease is increasing in popularity, largely because it works, and word of effective treatments travels fast in a rare disease community. While there is no firm answer for why it helps, there is a reasonable explanation: it treats both deconditioning and POTS and many mast cell patients have one or both.  I wrote a seven part series on why exactly intravenous fluids help in these situations. I have also written in great detail about the way that mast cell disease and POTS interact.

A paper published in early 2017 reestablished the finding that use of intravenous fluids helps POTS. Treatment lengths and infusion volumes varied from person to person. Despite these variations, use of IV fluids decreased symptoms and improved quality of life for POTS patients. The link to the abstract is here.

Many mast cell mediators are vasoactive, affecting the permeability of blood vessels. This means that mast cell activation causes third spacing, the loss of fluid from the bloodstream to the tissues, where the body cannot use it. This functional dehydration can cause a lot of symptoms, not the least of which is exhaustion and difficulty standing or exercising. For obvious reasons, this will be further exacerbated in a patient that is deconditioning or who has also has POTS.

Orthostatic symptoms can be very activating to patients and managing them effectively can help significantly. I have seen IV fluids work where more traditional methods like drinking lots of fluids and consuming lots of salt, or medications like fludrocortisone have not helped. Additionally, the first line tools for managing POTS, beta blockers, are contraindicated in patients at increased risk for anaphylaxis and therefore in people with mast cell disease.

I am a fervent supporter of IV fluids (also called volume loading) in the context of mast cell disease. I have seen it stabilize patients and reduce the frequency of anaphylaxis and severe symptoms, especially orthostatic symptoms and GI symptoms.

I personally use IV fluids. If I don’t receive IV fluids at least three times a week, my orthostatic symptoms become so severe that it is difficult to stand or even move. This in turn triggers mast cell reactions. The benefits of IV fluids to my personal health are significant. Many patients report the same.

While I support the use of IV fluids in the context of mast cell disease, patients should be aware that there are infection risks associated with repeated IV access or placement of a central line. The risks are much lower for repeated IV access as central lines have a host of other risks, including blood clots, and infections have the potential to be much more serious. However, IV access can be difficult for mast cell patients. The treatment value of IV fluids should be weighed on a case by case basis and IV access on a case by case basis.

For additional reading, please visit the following posts:

Deconditioning, orthostatic intolerance, exercise and chronic illness: Part 1

Deconditioning, orthostatic intolerance, exercise and chronic illness: Part 2

Deconditioning, orthostatic intolerance, exercise and chronic illness: Part 3

Deconditioning, orthostatic intolerance, exercise and chronic illness: Part 4

Deconditioning, orthostatic intolerance, exercise and chronic illness: Part 5

Deconditioning, orthostatic intolerance, exercise and chronic illness: Part 6

Deconditioning, orthostatic intolerance, exercise and chronic illness: Part 7

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 12

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 31

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 32

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 74

I get asked a lot about how mast cell disease can affect common blood test results. I have broken this question up into several more manageable pieces so I can thoroughly discuss the reasons for this. The next few 107 series posts will cover how mast cell disease can affect red blood cell count; white blood cell count, including the counts of specific types of white blood cells; platelet counts; liver function tests; kidney function tests; electrolytes; clotting tests; and a few miscellaneous tests.

  1. How does mast cell disease affect red blood cell counts?

There are several ways in which mast cell disease can make red blood cell count lower.

  • Anemia of chronic inflammation. This is when chronic inflammation in the body affects the way the body absorbs and uses iron. It can result in iron deficiency. Iron is used to make hemoglobin, the molecule used by red blood cells to carry around oxygen to all the places in the body that need it. If there’s not enough iron to make hemoglobin, the body will not make a normal amount of red blood cells.
  • Vitamin and mineral deficiencies. Like I mentioned above, chronic inflammation can affect the way your body absorbs vitamins and minerals through the GI tract, and the way it uses vitamins and minerals that it does absorb. While iron deficiency is the most obvious example of this, deficiency of vitamin B12 or folate can also slow red cell production.
  • Swelling of the spleen. This can happen in some forms of systemic mastocytosis, and may also happen in some patients with mast cell activation syndrome, although the reason why it happens in MCAS is not as clear. Swelling of the spleen can damage blood cells, including red blood cells, causing lower red blood cell counts. If the spleen is very stressed and working much too hard, a condition called hypersplenism, the damage to blood cells is much more pronounced. This may further lower the red blood cell count. Hypersplenism occurs in aggressive systemic mastocytosis or mast cell leukemia. It is not a feature of other forms of systemic mastocytosis and I am not aware of any cases as a result of mast cell activation syndrome.
  • Medications. Some medications that are used to manage mast cell disease can cause low red blood cell count. Chemotherapies, including targeted chemotherapies like tyrosine kinase inhibitors, can cause low red blood cell count. Medications that specifically interfere with the immune system can do the same thing, including medications for autoimmune diseases like mycophenolate. Non steroidal anti-inflammatory drugs (NSAIDs) are used by some mast cell patients to decrease production of prostaglandins. They can interfere with red blood cell production in the bone marrow and also cause hemolytic anemia, when the immune system attacks red blood cells after they are made and damages them.
  • Excessive bleeding. Mast cell disease can cause excessive bleeding in several ways. Mast cells release lots of heparin, a very potent blood thinner that decreases clotting. This makes it easier for the body to bleed. It is not unusual for mast cell patients to have unusual bruising. Bleeding in the GI tract can also occur. Mast cell disease can cause ulceration, fissures, and hemorrhoids, among other things. Mast cell disease can contribute to dysregulation of the menstrual cycle, causing excessive bleeding in this way.
  • Excessive production of other types of blood cells. In very aggressive forms of systemic mastocytosis, aggressive systemic mastocytosis or mast cell leukemia, the bone marrow is making huge amounts of mast cells. As a result, the bone marrow makes fewer cells of other types, including red blood cells. Some medications can also increase production of other blood types, causing less production of red cells. Corticosteroids can do this.
  • Excess fluid in the bloodstream (hypervolemia). In this situation, the body doesn’t actually have too few red blood cells, it just looks like it. If your body loses a lot of fluid to swelling (third spacing) and that fluid is mostly reabsorbed at once, the extra fluid in the bloodstream can make it look like there are too few red cells if they do a blood test. This can also happen if a patient receives a lot of IV fluids.

There are also a couple of scenarios where mast cell disease can make the red blood cell count higher. This is much less common.

  • Chronically low oxygen. If a person is not getting enough oxygen for a long period of time, the body will make more red blood cells in an effort to compensate for the low oxygen. This could happen in mast cell patients with poor oxygenation.
  • Third spacing. If a lot of fluid from the bloodstream becomes trapped in tissues (third spacing), there is less fluid in the bloodstream so it makes it look like there are too many cells. As I mentioned above, this is not really a scenario where you are making too many red blood cells, it just looks like that on a blood test.

For additional reading, please visit the following posts:

Anemia of chronic inflammation

Effect of anemia on mast cells

Effects of estrogen and progesterone and the role of mast cells in pregnancy

Explain the tests: Complete blood cell count (CBC) – Low red cell count

Explain the tests: Complete blood cell count (CBC) – High red cell count

Explain the tests: Complete blood cell count (CBC) – Red cell indices

Gastrointestinal manifestations of SM: Part 1

Gastrointestinal manifestations of SM: Part 2

Mast cell disease and the spleen

Mast cells, heparin and bradykinin: The effects of mast cells on the kinin-kallikrein system

MCAS: Anemia and deficiencies

MCAS: Blood, bone marrow and clotting

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 3

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 12

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 19

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 20

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 45

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 72

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 73

Third spacing

The MastAttack 107: The Layperson’s Guide to Mast Cell Diseases, Part 12

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

20. Why do a lot of mast cell patients get intravenous (IV) fluids?
• Use of IV fluids is becoming increasingly common for mast cell patients as word spreads that it helps with fatigue, overall energy, and general reactivity.
There have not been any studies showing that IV fluids work directly for mast cell disease. However, there have been papers demonstrating that it helps with deconditioning (when your body is out of shape from being sick), POTS (which a lot of mast cell patients have), and other chronic illnesses.
• A lot of chemicals that mast cells release can cause some of the liquid in your bloodstream to fall out through the walls of the bloodstream and become trapped in the tissues there. This phenomenon is called third spacing.
• The term “third spacing” is derived from the idea that fluids like blood or other fluids can be in one of three “spaces” in the body. One space is inside the cells, where cells can use it. Another space is right outside the cells, where cells can still use it. When fluids are stuck in a place that can’t be used by cells, and therefore is not useful to the body, it is said to be in a third space. So third spacing is when the fluids your body needs is stuck in the wrong place.
Third spacing is the cause of most types of swelling and edema.
• When you have fluid that should be in your bloodstream stuck in a third space, you are functionally dehydrated. This is important because bloodwork may not always show that you are truly dehydrated when you have a lower amount of third spacing but you will still have a lot of the symptoms of it.
IV fluids puts more fluids back into the blood to compensate for the fluids that get sucked out of the bloodstream and aren’t useful to the body. When this fluid is replaced, it helps stabilize blood pressure and heart rate. It also takes stress off many other cells so they calm down too, calming down mast cells.

For more detailed reading, please visit this post:

Third spacing

I also wrote a seven part series on third spacing and IV fluids. The first post is here.


Deconditioning, orthostatic intolerance, exercise and chronic illness – Part 7

A number of studies have investigated whether loading with intravenous hydration solutions (saline, etc) or with a volume expander such as dextran can ameliorate symptoms associated with deconditioning. These studies have found that volume expansion (also called fluid or volume loading) can improve a number of symptoms in deconditioned patients, but does not improve exercise capacity. Multiple studies have found the best effects from intravenous saline in conjunction with exercise.

Shibata investigated whether orthostatic intolerance could be mitigated following bed rest with exercise and/or fluid loading (Shibata 2010). This study found that OI could be dextran solution (IV fluids) given after twenty days of bed rest was insufficient to control OI symptoms, but that it was successful when used in conjunction with a daily exercise program. This finding was important, as it indicated that low blood volume was not the exclusive factor in orthostatic intolerance.

Figueroa et al looked at the relationship between blood volume and exercise capacity in POTS patients (Figueroa 2014). They found that acute volume loading with IV saline reduces heart rate and improves orthostatic tolerance and other symptoms in POTS patients. Importantly, IV saline significantly increased the stroke volume, cardiac output and reduced systemic vascular resistance. However, IV saline did not affect peak exercise capacity or improve cardiovascular markers during exercise. So while IV saline does help symptoms in these deconditioned patients, it does not improve exercise capacity. The author notes that for this purpose, acute infusion may not be sufficient and may need to undergone chronically to see benefits on exercise physiology.

Whole body heating is known to increase cardiac output, constrict the blood vessels in the abdominal cavities, increase sympathetic nerve activity in the muscles and decrease vascular resistance in the skin. Taken together, these factors stress the regulatory mechanism of the cardiovascular system. One study (Keller 2009) found that acute expansion of blood volume (with dextran) completely mitigated the impact of heat stress on orthostatic tolerance. In short, receiving an infusion that increased the blood volume allowed the cardiovascular system to function properly in the face of a known stressor.

One study looked at the effect of fluid loading on orthostatic intolerance and blood flow in the brain (Jeong 2012). They found that following bed rest, volume loading alone prevented larger reductions in cerebral blood flow, but did not prevent orthostatic intolerance. Exercise and volume loading prevented orthostatic intolerance but did not affect cerebral blood flow. Importantly, aerobic or resistance exercise before bed rest did not prevent development of decompensation.

A 2000 paper notes that POTS symptom scores improved significantly following administration of IV saline (Gordon 2000). Additionally, a 2013 study evaluated the frequency and characterization of “brain fog”, a common term for the cognitive deficits associated with this (and other) conditions (Joyner 2013). 86% (56/66) of patients reported that IV saline was the most effective treatment for brain fog.

In summary, bolus IV fluids or volume expanders have been found to improve a number of symptoms in deconditioned patients, although they have not been found to improve exercise capacity. For this metric, a graded exercise program is recommended. 

(Author’s note: I have recently been made aware that the data supporting use of graded exercise for chronic fatigue patients was hugely flawed. I retract this statement at this time. For details on this topic, please refer to this Lancet article:

A 2008 paper compared POTS and deconditioning (Joyner 2008). The author pointed out that a number of parallels existed between the physiological changes seen in POTS patients and those seen in deconditioned patients. Additionally, he made note of the parallels between POTS, chronic fatigue syndrome and fibromyalgia and the fact that exercise training had seen benefits in all of them. Given the significant relationship between mast cell disease and POTS, and the large overlap in CFS, fibromyalgia and mast cell populations, it is a comfortable assumption that an effective treatment modality for CFS, POTS and fibromyalgia may also be effective for mast cell disease. It is my belief that this is the basis for the frequently discussed finding of mast cell patients that intravenous fluids ameliorate a number of symptoms.

Furthermore, there are special considerations for mast cell disease that make intravenous fluids likely to cause a positive change in symptom profile. The first is that mast cell degranulation can induce systemic effects on arterial tone, hypotension and vasodilation (Willingham 2009). The next is that hypotension is characteristic of systemic mastocytosis, and that hypotension and syncope may occur due to cerebral hypoperfusion (Ozdemir 2010). Lastly, it is well known that mast cell mediators, including histamine, serotonin and tryptase, can induce capillary leakage leading leading to edema, and that they can increase vascular permeability (He 1997). Taken together, these points indicate that a mast cell patient may lose volume from the bloodstream into the surrounding tissues, which can exacerbate an already existing tendency toward hypotension, in turn made worse by orthostatic intolerance.

Fluid loading in the form of intravenous fluids may decrease symptoms in mast cell patients due to deconditioning, orthostatic intolerance and the capillary leakage often seen as a result of mast cell disease, which is especially present following mast cell attacks and anaphylaxis.



Gordon VM., et al. Hemodynamic and symptomatic effects of acute interventions on tilt in patients with postural tachycardia syndrome. Clin Auton Res. 2000 Feb; 10(1): 29-33.

Ross, Amanda J., et al. What is brain fog? An evaluation of the symptom in postural tachycardia syndrome. Clin Auton Res 2013 Dec; 23(6): 305-311.

Raj, Satish R., et al. Postural orthostatic tachycardia syndrome (POTS). Circulation 2013; 127: 2336-2342.

Rocío A. Figueroa, et al. Acute volume loading and exercise capacity in postural tachycardia syndrome. J Appl Physiol 117:663-668, 2014.

He, Shaoheng, Walls, Andrew F. Mast cell activation may be all that is sufficient and necessary for the rapid development of microvascular leakage and tissue edema. European Journal of Pharmacology 1997; 328(1): 89-97.

Ozdemir, D., et al. Hypotension, syncope and fever in systemic mastocytosis without skin infiltration and rapid response to corticosteroid and cyclosporine: a case report. Case Reports in Medicine, Volume 2010 (2010), Article ID 782595.

Willingham DL, et al. Unexplained and prolonged perioperative hypotension after orthotopic liver transplantation: undiagnosed systemic mastocytosis. Liver Transpl 2009 Jul; 15(7): 701-8.

Keller, David M., et al. Acute volume expansion preserves orthostatic tolerance during whole body heat stress in humans. J Physiol 2009 Mar; 587(5): 1131-1139.

Sung-Moon Jeong , Shigeki Shibata , Benjamin D. Levine , Rong Zhang. Exercise plus volume loading prevents orthostatic intolerance but not reduction in cerebral blood flow velocity after bed rest. American Journal of Physiology – Heart and Circulatory Physiology 2012 Vol. 302 no. 2.

Shizue Masuki , John H. Eisenach , William G. Schrage , Christopher P. Johnson , Niki M. Dietz , Brad W. Wilkins , Paola Sandroni , Phillip A. Low , Michael J. Joyner. Reduced stroke volume during exercise in postural tachycardia syndrome. Journal of Applied Physiology 2007 Vol. 103 no. 4, 1128-1135.






Do all mast cell patients need central lines? No. But some do.

A newer patient asked a couple of days if everyone with mast cell disease needs a PICC line, Broviac/Hickman or port for IV access. The answer is no, but I think we should talk about this a bit.

Central lines are usually given for people who need chemo or long term IV treatmet. These lines are not really designed to be left in your body forever, even ports. They generally are pulled once treatment is done, although ports can be left in for years as long as they are flushed monthly.

In my experience, mast cell patients get central lines for a few reasons:

  1. They have very poor IV access, so poor that it could delay treatment in an emergency (anaphylaxis).
  2. They get regular IV medications (this is not very common, although it’s hard to tell in this group).
  3. They regularly take IV medication that can damage veins if given frequently in peripheral veins (like Benadryl).
  4. They get them for IV hydration (it is not recommended to get a central line just for IV hydration, however some people do get them).

In the groups, it seems like there are so many patients who have these lines. Please keep in mind that those with more disabling disease are the most likely to be present in those forums. This group often also has other diagnoses for which central lines may be beneficial. On the other hand, the other group that is quite visible is the rookies. So the new patients see this very severe face on a disease which is quite manageable for many. You are seeing a subset of the population. Central lines in the mast cell community are not as common as it seems.

Regarding IV hydration, there are a few reasons why people receive this. Some of us vomit frequently and so fluids are difficult to get into us orally. Some of us have POTS or dysautonomia and have low blood volume, so the IV hydration stabilizes our blood pressure and heart rate. Some of us third space badly, and oral fluids end up in the wrong place.

This patient asked if they could just drink fluids. The answer is absolutely yes. If you can keep oral fluids down and are functioning, then I would do that. Receiving regular IV fluids can help with some symptoms, but there is no reason they need to be delivered through a central line. I used to get IV fluids at the infusion center with a new IV everytime. It is a pain but it’s not awful.

In an acute situation, IV fluids can be very helpful to mast cell patients. Long term, you need to be monitored properly as it can affect your electrolytes and for some this may raise kidney concerns. I would not get IV fluids based simply upon “feeling dehydrated”. If you “feel dehydrated” and also your blood pressure is wacky and you can’t keep down oral fluids, I think that then regular IV hydration might be useful.

I know it is frustrating to feel that you are not doing as well as you used to, but if you have mast cell disease, it is very possible you never will again, even with IV fluids. I am sorry, but that is the reality. You need to adapt to the level of ability you can manage currently.  Get some stability and things will improve.

If you and your doctor feel that IV hydration is appropriate, I would try it outpatient for a few weeks. If they then feel you need to do it at home, placing a PICC line is a good place to start. If you have a problem with the PICC line, it can be pulled without much trouble. The other lines are implanted and require surgery to remove them. The risk of bloodstream infections from central lines is real and these are very serious situations with long term effects.

Mast cell patients also run the risk of reacting to the materials used to make the line. They can also react to the maintenance of the line, such as flushing, use of heparin and alcohol swabs. This is a real problem for some people. So any time you can avoid an indwelling line long term, that is the better option.

Lastly, central lines require maintenance so you need to be sure that if your doctor wants to order one, they will also order the solutions and nursing care needed to keep you safe.